An electronics module, such as those used in airplanes for enabling them to operate, e.g. by providing them with calculation resources, comprise a box with housings, each of which receives an electronics card. The box is usually provided with ventilation grids arranged to create a flow of a total stream of air between two opposite faces of the box in such a manner that identical fractions of the stream of air pass through the respective housings in order to cool the electronics cards received in said housings.
It is known that the total stream of air that is to cool the electronics cards contained in the module can be defined, e.g. by adapting the size of the ventilation grids.
Unfortunately, not all electronics cards produce the same quantities of heat, such that the cooling created by uniformly sharing the total stream of air between the housings is not necessarily matched to the electronics cards.
In addition, in certain applications in the field of aviation, the electronics modules are grouped together in bays and they share the ventilation means of the bay. Standards set numerous characteristics of the electronics module, and in particular the flow rate of air and the head loss associated with ventilating the electronics module, and also the positioning of air inlets and outlets . . . imposing an air flow rate and a maximum temperature for the air at the outlet of the module in order to ensure that each module can benefit from a stream of air that is suitable for cooling its components.
An electronics module is also known that has a device for adjusting the total stream of air, which device is placed facing one of the ventilation grids.
Once more, the modified electronics module is thus characterized as a whole by a certain total cooling capacity that is not necessarily appropriate for all of the electronics cards. In addition, once the cards are in place in the electronics module, the adjustment device is difficult to access, thus making it awkward to adjust the total stream of air. Furthermore, the range over which the total stream of air can be varied is found to be limited.